Autism Linked To Air Pollution Exposure During Pregnancy

Pregnant women who were exposed to high levels of air pollution
were twice as likely to have a child with autism as women who
lived in low pollution areas, according to a US study.

Experts at Harvard University said they had reached worrying
conclusions over the elevated risk of autism in more polluted
areas, in what they said was the first large national to examine
links between the prevalence of pollution and the development of
the developmental disorder.

The findings are published in the journal Environmental Health
Perspectives.

"Our findings raise concerns," said lead author Andrea Roberts, a
research associate in the Harvard School of Public Health
Department of Social and Behavioral Sciences.

"Depending on the pollutant, 20 percent to 60 percent of the
women in our study lived in areas where risk of autism was
elevated," she said.

The data came from a large survey of 116,430 nurses that began in
1989.

For the analysis, researchers isolated 325 women who had a child
with autism and 22,000 women who had a child without the
disorder.

To estimate exposure to pollutants while pregnant, they used air
pollution data from the Environmental Protection Agency, and
adjusted for factors like income, education, and smoking during
pregnancy.

The analysis found that women who lived in locations with the
highest levels of diesel particulates or mercury in the air were
twice as likely to have a child with autism as those who lived in
the areas with the lowest levels.

When the pollutants included lead, manganese, methylene chloride
and combined metal exposure, women in areas with the highest
levels of these pollutants were about 50 percent more likely to
have a child with autism.

Autism is a brain disorder that affects as many as one in 88 in
the United States, and about one in 100 in Britain.

Researchers said the findings suggest that metals and other
pollutants should be regularly measured in the blood of pregnant
women to give a better understanding of whether certain
pollutants increase autism risk.